Of course they will eventually need light or die. It's the same like if you got no food. You will starve, but you can "digest yourself" first to prevent dying before getting something to eat. Similarly plants can grow without sunlight. They actually grow even more (taller). That's classical response of young seedlings which must ensure by this way they will reach the sunlight from soil with help of nutrients from the seed.

Sansaveria (mother-in-law tongue) can do well in very low light situations. Which plants do best without...depends on whether they are dormant or not. Some plants if dormant can last a long time between growing seasons.